The surgeon who desires an atlas of techniques covering operations on the colon and rectum almost surely prefers a concise volume rather than an encyclopedic compilation of the innumerable procedures that have been described in the literature. This book includes the operations that have proved to be useful and have survived the test of time. They now are in general use in the Massachusetts General Hospital. Space limitations have necessitated exclusion of detailed illustrations of a number of infrequently performed procedures, such as pelvic exenter ation for cancer of the rectum. In such instances bibliographic references have been provided for ready reference. The bibliography emphasizes recent contributions because they are easily available to the reader. Critical comments by the authors concerning certain technical pro cedures may be due to personal bias and certainly do not imply that the alternative methods are undesirable. Furthermore, the brevity of discus sion of anatomy, physiology, and pathology and the neglect of details of medical therapy of numerous colorectal diseases must be attributed to the fact that this volume is directed primarily toward the practicing surgeon. Thanks are due to the artists Mrs. Edith Tagrin and Mr. Robert Galla, and to Miss Evelyn Hall for help in the preparation of the manuscript. Claude E. Welch, M.D. Leslie W. Ottinger, M.D. John P. Welch, M.D. .